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This paper describes recent progress in our program to develop an emissions technology allowing diesel engines to meet the upcoming 2007/2010 regulations for NOx. At the heart of this technology is the ArvinMeritor Diesel Fuel Reformer that reforms the fuel, on-demand, on-board a vehicle. The fuel reformer uses plasma to partially oxidize a mixture of diesel fuel and air creating a highly reducing mixture of Hydrogen and Carbon monoxide. In a previous publication, we have demonstrated that using a reformate rich in H2 and CO to regenerate a NOx trap is highly advantageous compared to vaporized diesel fuel used conventionally. In this paper we present results and a strategy for performing desulfation of the traps using the fuel reformer. In contrast to vaporized diesel, which requires very high temperatures that fall outside the normal exhaust operating temperatures for diesel engines, desulfation was achieved at temperatures lower by more than 100 °C using the Plasma Fuel Reformer.

An active diesel particulate filter regeneration system has been developed to remove diesel particulate matter (PM) accumulation from diesel particulate filters. Diesel particulate filters (DPF) are an effective means of significantly reducing PM emissions from vehicles powered by diesel engines. This paper outlines the use of the ActiveClean™ Thermal Regenerator (TR) system to reduce PM emissions in several different applications. Test cell data was collected using a 15.8L diesel engine to provide exhaust flow. The objective of this test was to evaluate the steady state HC, CO and NOx emissions of the engine and TR combination during regeneration of the filter. The data reveals only a slight increase in HC and CO emissions depending on configuration (single-or dual-leg) for steady state regenerations. It also showed that the TR had very little impact on NOx emissions during regeneration.

In order to enable the regeneration of NOx traps at low temperatures and reduce the fuel penalty, an innovative fuel reformer has been developed to create a hydrogen-rich gas from diesel fuel to be used as the NOx reductant. This paper outlines the experimental use of this hydrogen generation device on a dual-leg NOx trap system with an 8.3L diesel engine. The system was tested at six ESC modes, and gave satisfactory results at those engine conditions where the NOx trap had good adsorption capacity (exhaust temperature < 450 °C). With the NOx conversion efficiency of 80% as the target, the fuel economy penalty was about 3% for most engine conditions. Since this type of diesel engines are widely used for urban transit buses, the system was also tested at six typical road conditions and showed satisfactory results in terms of both NOx conversion efficiency and fuel economy penalty. A comparison with diesel fuel as the NOx reductant was conducted with the same test setup.

Catalytic converters are typically constrained and cushioned by an intumescent mat material that is critical to the durability of the ceramic and metallic substrates. In an effort to reduce costs and improve designs, this work attempts to develop and verify a material model for the mat that can be utilized in predictive analysis. Test data are used in conjunction with the finite element program ABAQUS™ to create both a hyperfoam and a user-defined material model. These models will be verified and compared by modelling with ABAQUS the specimens and test conditions used to generate the data.

The Fuzzy Inference System Translator (FIST) is a tool in the realization of standalone, fully-programmable, fuzzy logic micro-controllers for the regulation of advanced life support system temperature and humidity subsystems. Analog input signals may include chamber temperature, relative humidity, CO2 concentration and nutrient level. Analog output signals can be, for example, heater voltage and condensing heat-exchanger cold-water valve voltage, nutrient pump actuator voltage and grow-lamp actuator voltage. Features of the micro-controller described, include keypad entry of sensor calibration data and online modification of the photo-period, temperature, humidity and CO2 levels during full system operation. All system inputs and outputs can be selected for read-out on a liquid crystal display (LCD).